AbstractSome objects in your application simply describe attributes of other objects. These objects can be modeled as Value Objects, immutable and without identity. In this article, Steve introduces Value Objects and shows an example of how to implement them in a simple design.

A Value Object is an object that has no unique identity, but
rather represents a characteristic of something else. For instance, the
integer 7 can be used anywhere and always means the same thing - we don't think
about this or that particular instance of the integer 7. Likewise, a given
date like 11 July 2011 (GMT) is the same everywhere - it has no additional
identity. In designing systems, it's useful to identify parts of the design
that should be represented as Value Objects, as opposed to Entities, which each
have a unique identity.

Title:
More Design Patterns
Name:
Steve Smith
Date:
2011-07-15 11:50:34 AM
Comment: I talk more about design patterns on my blog where I have a ton of links to more resources. Check it out here:Common Design Patterns - Resourceshttp://stevesmithblog.com/blog/common-design-patterns-resources/